Re: [PATCHv2 0/8] btrfs: Create macro to iterate slots

[Marcos Paulo de Souza <mpdesouza@suse.de>]

On Thu, 2021-08-26 at 13:40 -0300, Marcos Paulo de Souza wrote:
> There is a common pattern when search for a key in btrfs:
> 
>  * Call btrfs_search_slot
>  * Endless loop
>      * If the found slot is bigger than the current items in the
> leaf, check the
>        next one
>      * If still not found in the next leaf, return 1
>      * Do something with the code
>      * Increment current slot, and continue
> 
> This pattern can be improved by creating an iterator macro, similar
> to
> those for_each_X already existing in the linux kernel. using this
> approach means to reduce significantly boilerplate code, along making
> it
> easier to newcomers to understand how to code works.
> 
> This patchset survived a complete fstest run.

My bad, I only added v2 to the cover-letter, but the only change from
v1 is that now the xattr changes are in a separate patch.

> 
> Changes from v1:
>  * Separate xattr changes from the macro introducing code (Johannes)
> 
> Changes from RFC:
>  * Add documentation to btrfs_for_each_slot macro and
> btrfs_valid_slot function
>    (David)
>  * Add documentation about the ret variable used as a macro argument
> (David)
>  * Match function argument from prototype and implementation (David)
>  * Changed ({ }) block to only () in btrfs_for_each_slot macro
> (David)
>  * Add more patches to show the code being reduced by using this
> approach
>    (Nikolay)
> 
> Marcos Paulo de Souza (8):
>   fs: btrfs: Introduce btrfs_for_each_slot
>   btrfs: block-group: use btrfs_for_each_slot in
> find_first_block_group
>   btrfs: dev-replace: Use btrfs_for_each_slot in
>     mark_block_group_to_copy
>   btrfs: dir-item: use btrfs_for_each_slot in
>     btrfs_search_dir_index_item
>   btrfs: inode: use btrfs_for_each_slot in btrfs_read_readdir
>   btrfs: send: Use btrfs_for_each_slot macro
>   btrfs: volumes: use btrfs_for_each_slot in btrfs_read_chunk_tree
>   btrfs: xattr: Use btrfs_for_each_slot macro in btrfs_listxattr
> 
>  fs/btrfs/block-group.c |  33 +-----
>  fs/btrfs/ctree.c       |  28 ++++++
>  fs/btrfs/ctree.h       |  25 +++++
>  fs/btrfs/dev-replace.c |  51 ++--------
>  fs/btrfs/dir-item.c    |  27 +----
>  fs/btrfs/inode.c       |  46 ++++-----
>  fs/btrfs/send.c        | 222 +++++++++++--------------------------
> ----
>  fs/btrfs/volumes.c     |  23 ++---
>  fs/btrfs/xattr.c       |  40 +++-----
>  9 files changed, 169 insertions(+), 326 deletions(-)
>